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NRC proposes changes to its rules on nuclear materials
In response to Executive Order 14300, “Ordering the Reform of the Nuclear Regulatory Commission,” the NRC is proposing sweeping changes to its rules governing the use of nuclear materials that are widely used in industry, medicine, and research. The changes would amend NRC regulations for the licensing of nuclear byproduct material, some source material, and some special nuclear material.
As published in the May 18 Federal Register, the NRC is seeking public comment on this proposed rule and draft interim guidance until July 2.
Jacob B. Romero
Nuclear Science and Engineering | Volume 42 | Number 1 | October 1970 | Pages 49-57
Technical Paper | doi.org/10.13182/NSE70-A19326
Articles are hosted by Taylor and Francis Online.
Radioactive particles escaping a surface carry a portion of the disintegration energy. The fluxes of particles, power, and energy are referred to as residual fluxes. In this paper a method is formulated for predicting residual fluxes emanating from a composite surface consisting of an active substrate layer protected by a clad layer. Application of this method requires only knowledge of the particle ranges in the layer materials. Using existing range-energy equations, generalized plots are presented for estimating residual quantities for heavy particles. Calculations show that fractional residual power and particle fluxes vary from 0.5 for thin (monoatomic) layers to zero for very thick layer or heavily cladded systems. Typical values of the residual power are 0.1 W/cm2 for alpha particles and 10 W/cm2 for fissioning surfaces.